#include <iostream>

using std::cout;
using std::endl;

//将构造函数设置为protected的类，称为抽象类(第二种形式)
//抽象类也是不能创建对象的
class Base
{
/* public: */
/* private: */
protected:
    Base()
    {
        cout << "Base()" << endl;
    }
};

class Derived
: public Base
{
public:
    Derived()
    : Base()
    {
        cout << "Derived()" << endl;
    }

};

int main(int argc, char *argv[])
{
    /* Base base; */
    Derived derived;
    return 0;
}

